Combined liner hanger and well casing sealing device and method for completing wells



Jan. 16, 1968 F. E. CHANCELLOR ETAL 3,363,694

COMBINED LINER HANGER AND WELL CASING SEALING DEVICE AND METHOD FOR COMPLETING WELLS File-d June 21, 1965 3 Sheets-Sheet l ROBERT O. CHANCELLOR IN VEN TORS Arrok'lvers FORREST E. CHHNCELLOR Jan. 16, 1968 F. E. CHANCELLOR ETAL 3,363,694

COMBINED LINER HANGER AND NE-LL CASING SEALING DEVICE AND METHOD FOR COMPLETING WELLS \Y/0R FORREST E. CHANCELLOR ROBERT o. CHANCELLOR lN'VENTO/PS Jan. 1 1

968 F. E- CHANCELLOR ETAL COMBINED LINER HANGER AND WELL CASING SEALING DEVICE AND METHOD FOR COMPLETING WELLS Filed June 21, 1965 3 Sheets5heet L5 [6.5 FORREST E. CHMNCELLUJQ 3R RCWEQT O. C/MNCELLO/P INVENTORS A TTO/P/VEVS United States Patent C) COMEHNED LINER HANGER AND WELL CAS- lNG SEALING DEVICE AND METHOD FOR COREPLETENG WELLS Forrest E. Chancellor and Robert 0. Chancellor, both of 2917 Pierce Road, Bakersfield, Calif. 93308 Filed June 21, 1965, Ser. No. 465,649 13 Claims. (Cl. 16649) ABSTRACT OF THE DHSCLOfiURE A well casing adapted to have a production liner disposed in suspended relation therefrom providing annular stop means disposed within the casing, and hanger means on the liner for engagement with said stop means to limit downward travel of the liner relative to the casing but permitting upward travel of the liner relative to the casing and free gravitational descent of the liner in response to thermal fluctuations in the well including the method of completing an oil well or the like with such apparatus by first utilizing said stop means with suitable packing tools to force cement and the like downwardly within the casing and thence upwardly into the well bore around the casing, partially removing said stop means and cleaning the casing by drilling, and inserting said liner into the casing with said hanger means rested upon said stop means and supporting the liner in said suspended rela tion from the casing.

The completion of oil wells frequently involves forcing cement downwardly through and around the well casing to seal the well here against the ingress of water when such water is present in the surrounding geological formation. This is usually accomplished by mounting a collar having a perforated inner portion, commonly known as a baffle plate, within a predetermined joint between adjacent sections of the well casing. The batlle plate permits the cement to pass downwardly therethrough and also affords a stop for suitable packing tools which are employed to force the cement downwardly and thence upwardly around the casing. After completing the cementing operation, the baflie plate is removed by drilling out the inner perforated portion thereof to a size corresponding to the inside diameter of the casing to permit the subsequent introduction of a perforated production liner and the additional oil well production equipment.

It has been recognized that rather than entirely removing the inner portion of the 'batlle plate, it might be utilized in supporting the production liner within the casing. Heretofore, it has been the practice to rest the lower end of the liner on the bottom of the well. With this method, however, the weight of the liner causes the sections thereof to kink, forming ledges within the liner which tend to impair the free movement of other Well tending equipment therethrough. Other known practices have utilized various hanger devices to suspend the liner from the lower end of the casing in spaced relation to the bottom of the well. All these devices employ some variety of toothed gripping members which are commonly known as hold-down slips. Consequently, a plurality of slips are usually pivotally or otherwise retractably mounted in circumferentially spaced relation about a mandrel or other mounting device secured to the upper end of the liner. The slips are releasably held in a retracted position during initial introduction of the liner within the casing by a drill tubing string to permit free movement of the liner relative to the casing. When the liner reaches the desired approximate setting position, the slips are released by rotation or other manipulation of a suitable control mechanism on the drill string to an expanded position Within the casing. During expansion, the teeth of the slips dig into the inner wall of the casing which upon further downward movement of the liner relative to the casing are positively set. Frequently, the slips fail to set themselves even after several manipulations of the liner alternately upwardly within the casing and downwardly to a positively set position. After such manipulation, the precise location of the liner is difficult accurately to determine inasmuch as the final setting position may be displaced a considerable distance from the original desired location. In this respect, slanted well bores are particularly troublesome in that the slips on the underside of the liner tend to catch and set more readily than the slips on the upper side of the liner. This usually results in the liner being disposed in a kinked or cocked position which again causes misalignment of the individual sections thereof and restricts free movement of the well tending and production equipment therethrough. However, once the slips are set within the casing, any further downward movement of the liner within the casing is prevented.

A major problem is thereby created in wells employing slip-type liner hangers when the well is subjected to thermal heating operations. These operations are employed for the secondary recovery of oil from low producing and abandoned oil wells. In an effort to revive such Wells, various procedures for heating the well cavity are currently employed. These include pumping hot water, steam and the like into the well or igniting combustible fuels in the well to reduce the viscosity of the heavier oil deposits and render them more readily recoverable. During these heating operations, the well casing and liner expand and retract relative to each other with the liner typically expanding upwardly within the well casing. The teeth of the slip-type hangers usually permit such upward movement of the liner but upon cooling and return downward movement immediately dig into the inner wall of the casing in a new setting position. Accordingly, after the liner cools, its normal contraction is limited by the reset slips farther up the casing. As a result, the contracting liner or casing is frequently fractured, causing considerable expense and delay repair and in some instances rendering the well totally unsalvable.

It is also common practice to provide a seal member about the liner hanger to restrict the interchange of fluid between the upper portion of the well casing containing the production equipment and the lower oil bearing portion of the well, particularly during Well flushing operations. These seals are usually constructed by pouring a lead ring in circumscribing relation about the liner hanger at the surface of the well before inserting the liner into the casing. The seal has an outside diameter somewhat larger than the inside diameter of the casing. Accordingly, during installation of the liner, the seal is forced into the casing and is slid the full length of the casing until the liner is disposed in its predetermined set position in depending relation from the lower end of the casing. Upon reaching the set position, the sealing surface of the seal ring may be entirely lost, particularly when the inner wall of the casing is roughened by cement deposits, scale and the like which renders the seal ineffective for the intended purpose.

Accordingly, it is an object of the present invention to provide an improved apparatus and method for completing wells.

Another object is to provide such an improved apparatus and method for completing wells which may be utilized during the described cementing operation and for subsequently supporting a production liner within the well casing.

Another object is to provide an apparatus of the char- 3 acter described which includes a combination bafiie plate and liner hanger stop collar.

Another object is to provide an apparatus and method for completing wells which permit controlled axial movement of the production liner within the well casing in response to thermal fluctuations occurring in the well.

Another object is to provide an apparatus and method for completing wells which include an improved liner sealing device.

Another object is to provide an apparatus and method for completing wells having a sealing device which is capable of being alternately retracted and automatically expanded incident to the setting of the liner in its desired position within the well.

Another object is to provide an apparatus for completing wells including a hanger device which insures precise centering of the liner within the casing even in slanted well bores.

Another object is to provide an apparatus for completing wells having such an improved liner hanger which is capable of setting the liner with a minimum of manipulation of the liner inserting tool.

Another object is to provide an apparatus and method wherein the liner hanger is capable of positively positioning the liner in the desired pro-selected position within the casing.

Another object is to provide an apparatus and method which enable the liner to be easily and conveniently removed from the casing.

Other objects and advantages of the present invention will subsequently become more clearly apparent upon reference to the following description and accompanying drawings.

In the drawings:

FIG. 1 is a central vertical section through a well bore and easing showing a combination bafiie plate and liner hanger stop collar mounted between adjacent sections of the casing supporting a bafiie plate for use during the initial cementing operation.

FIG. 2 is a side elevation of the entire apparatus of the present invention disposed within a well bore supporting a production liner from the combination b-aiile plate and liner hanger stop collar within the casing.

FIG. 3 is a somewhat enlarged side elevation of the liner hanger and seal device of the apparatus of the present invention with portions broken away for illustrative convenience shown in an initial supporting position prior to final setting.

FIG. 4- is a fragmentary transverse vertical section through the liner hanger and sealing device disposed in its final setting position with the seal expanded.

FIG. 5 is a somewhat enlarged transverse vertical section of the liner hanger providing an alternate sealing device shown in an initial non-sealing position.

FIG. 6 is a further enlarged fragmentary vertical section showing the liner hanger in a final setting position with the seal expanded in sealing relation against the casing.

FIG. 7 is a somewhat enlarged fragmentary transverse vertical section of the baffle plate of FIG. 1 rested upon the combination baffle plate and liner hanger stop collar.

Referring more particularly to the drawings, an apparatus for completing wells embodying the principles of the present invention is generally indicated by the reference numeral 10. The apparatus 10 is conveniently described in connection with an oil well providing an elongated well bore 12 extended downwardly within successive layers of oil bearing geological formations 14. An elongated tubular well casing 15 having a plurality of sections 16 interconnected by screw threaded couplings 17 is ex tended downwardly within the well bore and terminates in a lower open end 13.

The apparatus w of the present invention includes a combination baffle plate and liner hanger stop collar 20 which is adapted to be mounted between selected sections 16 of the casing 15 to dispose the stop collar at a predetermined desired depth within the well bore 12. As best shown in FIG. 1, the stop collar has an upper internally threaded end 21 screw threadably connected to the lower end of the upwardly adjacent casing section and an opposite externally screw threaded lower end 22 screw threadably received within the downwardly adjacent coupling 1/'. The stop collar further includes a centrally disposed bore 25 therethrough and an upper somewhat larger diameter counterbore 26 which form therebetween an annular shoulder or ledge 27. A lower counterbore 3% is formed within the lower end 22 of the stop collar of substantially the same diameter as the upper counterbore 26. The lower counterbore terminates short of the ledge 27 to form with the bore 25 an annular beveled shoulder or notch 32 tapered upwardly in cross section from the lower edge of the bore 25 to the lower counterbore 30.

As best shown in FIG. 7, a bafile plate 35 is adapted to be mounted within the batlle plate and liner hanger stop collar 2% at the surface of the well during assembly of the stop collar and sections 16 of the casing 15. The bathe plate is constructed of a lightweight metallic material such as aluminum or the like and is of a diameter slidably to be received within the upper counterbore 2-5 of the stop collar. The battle plate includes a lower annular surface 36 which is rested upon and supported by the ledge 27 of the stop collar and includes an upper annular flange 37 which extends beneath the lower end of the upwardly adjacent casing section. The baffle plate is normally only used in well bores extended through water bearing formations for utilization during the well cementing operation necessary in such well bores to pre vent water seepage into the oil producing zone of the well. After completion of the cementing operation, the bafi'ie plate is removed in a manner to be subsequently described so that the stomp collar 20 can be further utilized in performing the method of the present invention during the production liner setting operation for completing the well.

The apparatus 10 of the present invention further provides a liner hanger generally indicated by the reference numeral 46. The hanger includes an elongated tubular mandrel 42 which has a lower externally threaded end 43 and an opposite upper end 44-. An elongated tubular production liner 45 provides an upper internally threaded end 46 which screw threadably receives the lower end of the mandrel in tightly connecting suspended relation therefrom. The liner includes a lower end 47 which may be disposed at any desired depth within the well bore 12, which position may vary from approximately 50 to 400 feet from the bottom of the casing, depending upon the surrounding oil bearing formation. A plurality of perforations 48 are formed in the wall of the liner in substantially equally spaced rows circumferentially about the liner to permit the ingress of oil subsequently to be drawn or forced upwardly through the liner during production of the well.

A stop ring Si is disposed in circumscribing relation about the mandrel 42 in closely spaced relation to the upper end 44 of the mandrel and includes a plurality of circumferentially spaced axially extended grooves 52 in its outer peripheral surface 53. The stop ring is of a diameter freely to slide within the casing 15 with the grooves permitting the passage of any fluid within the casing passed the ring for ease of movement. As best shown in FIG. 3, the stop ring is temporarily rigidly connected in its described position on the mandrel by a plurality of rivets or pins 55 formed from any suitable relatively soft shearable material.

An annular sealing ring 66 which is preferably constructed of a relatively soft material such as brass is disposed in circumscribing relation about the mandrel immediately above the stop ring 50 so to rest against and be supported thereby when disposed within the casing.

The sealing ring is split to provide opposite overlapping ends 62 with the ring being movable between alternately retracted and expanded positions respectively shown in FIGS. 2 and 3. The inherent resiliency of the ring causes it normally to assume the partially expanded position of FIG. 3 in freely sliding engagement with the inner surface of the casing. However, the ring is readily collapsible to a retracted position with the ends 62 closed in fitted relation with each other and the ring intimately surrounding the mandrel for initial insertion into the casing 15. With the sealing ring in its partially expanded position, an annular space 64 is formed between the inner surface of the ring and the adjacent outer periphery of the mandrel. An expander ring 70 is disposed in circumscribing relation about the upper end 44 of the mandrel 42 above the sealing ring 60 and has a cross sectional thickness slightly greater than the width of the annular space 64 between the sealing ring and the mandrel. The expander ring has a lower beveled edge 72 which pilots the ex pander ring into the space 64 during the liner setting operation subsequently more fully described.

A setting nut mounting sleeve 75 is screw threadably mounted at 67 on the upper end 44 of the mandrel 42 and provides an outer grooved periphery 77 similar to the periphery of the stop ring 50 in freely sliding relation within the casing 15. The sleeve provides a lower annular surface 78 which is adapted to engage the upper surface of the expander ring 70 during the setting of the liner 45. The sleeve further provides internal left-handed screw threads 79 disposed above the upper end of the mandrel. A liner setting nut 85 is screw threadably received within the mounting sleeve 75 which provides a bore 87 therethrough having an enlarged cavity portion 88 centrally of the nut. The bore and cavity of the setting nut are adapted releasably to receive the end of a setting tool 90 which is commonly known as a Kelly. The setting tool is mounted on the lower end of a drill tubing string 92 which mounts a bumper sub 94 in closely spaced relation above the setting nut 85.

An annular tapered ring 100 is rigidly secured to the mandrel 42 in downwardly spaced relation from the stop ring, as by welding, at 102. The periphery of the ring tapers upwardly from a lower edge 103 to an enlarged upper edge 164, the latter of which is of a diameter easily to slide through the battle plate and liner hanger stop collar 20. A plurality of circumferentially spaced holddown fingers 11d constructed of a substantially flat spring steel material are rigidly mounted at their lower ends on the tapered ring by rivets or pins 112, formed of a suitable relatively soft metallic shearable material. The fingers are upwardly outwardly extended from the tapered periphery of the ring and terminate in upper ends 115 slidably engageable with the inner surface of the casing 15. It is to be noted that the spacing of the tapered ring and fingers from the stop ring 50 on the mandrel is predetermined by the distance of thermal expansion anticipated in the liner.

As best shown in FIGS. 5 and 6, an alternate form of sealing ring, indicated by the reference numeral 120, may be employed to replace the brass sealing ring 64). The sealing ring 120 is constructed preferably of lead and cooperates with the other previously described hanger components in substantially the same way as that previonsly described for the brass sealing ring. The sealing ring 124? provides beveled upper and lower edges 123 and 124, respectively. In this form, the setting nut sleeve 75 is modified to provide a beveled lower surface 126 and the stop ring 50 is modified to provide an upper beveled edge 128 which are both angled complementarily to their adjacent edges of the seal ring. A pair of axially spaced annular V-shaped grooves 139 are formed in the inner surface of the seal ring to insure uniform expansion of the ring against the inner surface of the casing during setting of the liner 45. The initial contracted position of the seal ring, as shown in FIG. 5, enables the ring to be slid the full length of the casing prior to expansion during said setting operation.

Operation The operation of the described embodiment of the subject invention is believed to be clearly apparent and is briefly summarized at this point. The baffle plate and liner hanger stop collar 20 and the baffle plate 35 are disposed within the casing 15 in the manner previously described so as to locate the stop collar at the predetermined desired depth within the well bore 12. The bafile plate may then be employed as a stop member for a suitable packing tool, such as a cementing plug or the like, not shown, to force the cement downwardly within the well bore and thence upwardly around the casing, as indicated at 132. After completion of the cementing operation, the bafile plate is removed by drilling downwardly through the stop collar to the desired depth below the casing. The drill size corresponds to the inside diameter of the stop collar so that the remaining flange portion 37 of the bafiie plate is sufiiciently reduced to insure its disintegration and complete removal from the casing.

The production liner 45 is connected. in the manner described to the liner hanger 40 and the entire assembly inserted and lowered into the casing 15 by the drill tubing string 92. The liner and liner hanger are suspended from the drill tubing string by the connection between the Kelly and the setting nut 85. It will be noted that the entire mechanism is freely slidable during such lowering of the liner into the casing until reaching the depth determined by the location of the stop collar 20. As the liner approaches the final portion of its downward travel, the tapered ring 1% slides through the stop collar with the fingers thereof flexing inwardly to pass through the collar, after which they return-flex outwardly against the inner wall of the casing in the section 16 of the casing below the stop collar which precisely disposes and holds the liner in centered position within the lower end of the casing. Such downward movement of the liner is terminated upon engagement of the lower surface of the stop ring 50 with the stop ledge 27 on the collar. The full weight of the liner is then supported through the ledge 27, the stop ring 50, and the shear pins 55. The drill tubing string 92 is then reciprocated which, by the lost motion provided by the Kelly setting tool 90 within the setting nut 85, enables the bumper sub 94 to strike the setting nut with sufficient force to shear the pins 55.

After the pins 55 are sheared, the liner 45 and mandrel 42 are permitted to slide downwardly within the stop ring 50 to the finally set position of FIG. 4. During such movement, the expander ring 70 is guided into the space 64 by its lower beveled edge 72. This positively expands the brass sealing ring 60 outwardly against the inner surface of the casing 15 while the inner surface of the expander ring is disposed in sealing relation against the periphery of the mandrel. This is accomplished through relative sliding movement between the expander ring and the mandrel until engaged by the lower surface 78 of the setting nut sleeve 75. It is significant that the brass sealing ring provides an effective seal throughout a wide range of expansive movement by the novel arrangement of its overlapping ends 62. The liner is thereby positively set in the predetermined desired position within the casing. Since the liner can only be lowered to the depth determined by the location of the stop collar, the setting of the liner requires no axial manipulation of the liner or the liner hanger 40 with the stop collar providing a positive check of the liner position to the operators at the surface of the well.

Alternatively, the lead sealing ring of FIGS. 5 and 6 may be utilized in place of the brass sealing ring 60. The sealing ring 120 is expanded in essentially the same manner upon shearing of the pins 55 to cause the entire weight of the liner and mandrel to be borne through the setting nut sleeve 75, the seal ring 120, and the stop ring 50. An additional downward force is imposed upon the setting nut sleeve through the drill tubing string 92 to compress the sealing ring to the reduced vertical dimension shown in FIG. 6. During such compressive movement, the sides of the grooves 13h are readily compressed toward each other which causes the outer periphery of the seal ring uniformly to expand outwardly in tightly sealing relation against the inner surface of the casing. Such outward expansion is further enhanced and controlled by the beveled edges 123 and 124 engaged by the correspondingly tapered edges of the setting nut sleeve and the stop ring.

The drill tubing string 92 is then rotated approximately eight turns to unscrew and release the setting nut 85 from the sleeve 75. The drill tubing string and setting nut are removed from the casing which completes the liner setting operation. Frequently, it is desirable to gravel pack the well bore around the liner which, although not herein described, can be accomplished through the hanger mechanism 40. The well casing is then in condition to receive the oil production equipment such as the pump and the like prior to well operation.

.During the previously described well bore heating operations, the liner is permitted to expand upwardly within the casing 15. During such expansion, the mandrel 42 slides upwardly through the stop ring and through whichever of the sealing rings or 120 is employed. As previously noted, the hold-down fingers lltl are set upon the mandrel in sufficiently spaced position from the stop collar 20 to accommodate expected liner travel during such heating operations. Upon nearing the end of such upward travel, the upper ends 115 of the fingers are received into the annular notch 32 of the stop collar to preelude additional upward movement of the liner. After the well bore has cooled, the liner is permitted free gravitational descent until fully returned to its suspended position within the casing with the stop ring 50 rested upon the ledge 27 of the stop collar.

It is apparent that in some well operations providing substantially vertical well bores, the hold-down fingers 110 may not be required so as to permit unlimited expansion of the liner upwardly in the casing. As previously noted, the hold-down fingers are particuarly applicable in slanted well bores so as positively to maintain the liner in centered relation within the casing. In such installations, if an excessive amount of liner expansion is experienced, the pins 112 mounting the fingers are easily sheared to prevent any damage to the liner or the casing. When it is desired completely to remove the liner from the well bore, the drill tubing string 92 is inserted and connected through the Kelly 90 and setting nut 85 to enable the finger pins 112 to be intentionally sheared by an upward pull on the drill tubing string.

In view of the foregoing, it is readily apparent that the apparatus of the present invention has provided an improved method for completing wells in its provision of a combination bathe plate and liner hanger stop collar which serves the dual function of supporting a baffle plate in predetermined position within the lower end of the well casing during well cementing operations and in addition is utilized for subsequently supporting a production liner in suspended relation from the casing. The liner hanger of the present invention readily combines with the stop collar to support the liner in optimum spaced relation from the bottom of the well and permits controlled axial movement of liner relative to the casing for accommodating thermal expansion and contraction without damaging or impairing the operation of such well components. Furthermore, the novel sealing arrangement between the liner and the well casing permits free sub stantially unrestricted insertion of the liner within the casing and is automatically expanded to a sealing position during the initial setting operation of the liner while permiting expansion and contraction of the liner without impairing the seal between the liner and the casing.

Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

1. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising annular stop means disposed in predetermined position within such a casing and having an annular shoulder extended radially inwardly thereof; hanger means borne by such a liner for engagement with said shoulder of the stop means to support the liner in suspended position from the casing and to limit downward travel of the liner relative to the casing but permitting substantially unrestricted upward travel of the liner incident to said thermal fluctuations in the well, and seal means initially carried on the liner adjacent to said hanger means and being permanently expandable in tightly sealing relation against said casing upon initial engagement of said hanger means with said shoulder of said stop means and thereafter permitting said liner free axial sliding movement therethrough during said thermal fluctuations in the well.

2. In combination with a well casing adapted to have a production liner suspended therefrom; an apparatus for slidably connecting said liner to the casing to accommodate thermal fluctuations in the well comprising annular stop means disposed in predetermined position within said casing; hanger means borne by said liner for engagement with said stop means to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; and resiliently flexible tension means mounted on said liner in axially spaced relation to said hanger means being expandable against said casin in sliding relation therewith to center the liner within the casing and being engageable with said stop means to limit upward travel of said liner relative to the casing.

3. In combination with a well casing adapted to have a production liner suspended therefrom, an apparatus for slidably connecting said liner to the casing to accommodate thermal fluctuations in the well comprising annular stop means disposed in predetermined position within said casing; hanger means borne by said liner for engagement with said stop means to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; seal means carried on the liner adjacent to said hanger means and being expandable in tightly sealing relation against said casing upon initial engagement of said hanger means with said shoulder of said stop means; and resiliently flexible tension means mounted 011 said liner in axially spaced relation to said hanger means being expandable against said casing in sliding relation therewith to center the liner within the casing and being engageable with said stop means to limit upward travel of said liner relative to the casing.

4. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination baffle plate and liner hanger stop collar rigidly mounted in predetermined position within said casing; a liner hanger borne by said liner having a stop ring engageable with said stop collar to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; and a seal ring carried on the liner up wardly adjacent to said stop ring for movement between a contracted position to permit free entry and sliding movement within the casing and an expanded position in tightly sealing relation against the casing incident to initial engagement of said stop ring against said stop collar with said liner being freely axially slidable through said stop ring and said seal ring during said thermal fluctuations in the well.

5. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination baflie plate and liner hanger stop collar rigidly mounted in predetermined position within said casing; a liner hanger borne by said liner having a stop ring engageable with said stop collar to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; a seal ringcarried on the liner upwardly adjacent to said stop ring for movement between a contracted position to permit free entry and sliding movement within the casing and an expanded position in tightly sealing relation against the casing incident to initial engagement of said stop ring against said stop collar with said liner being freely axially slidable through said stop ring and said seal ring during said thermal fluctuations in the well, and a plurality of resiliently flexible fingers mounted on said liner in downwardly axially spaced relation to said stop ring being expandable against said casing in sliding relation therewith to center the liner within the casing and being engageable with said stop collar to limit upward travel of said liner within the casing.

6. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination bafile plate and liner hanger stop collar rigidly mounted in predetermined position within said casing; a liner hanger borne by said liner having a stop ring engageable with said stop collar to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; 21 seal ring carried on the liner upwardly adjacent to said stop ring having radially contracted and expanded positions; and an expander ring borne by the liner above the seal ring for engagement with said seal ring to actuate said seal ring to said expanded position in tightly sealing relation against said casing upon initial engagement of said stop ring with said stop collar, and said liner being axially slidable through said stop ring, seal ring and expander ring during said thermal fluctuations in the well.

7. An apparatus, for slidably suspending a production liner from a Well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination baffle plate and liner hanger stop collar rigidly mounted in predetermined position within said casing; a liner hanger borne by said liner having a stop ring engageable with said stop collar to limit downward travel of the liner relative to the casing with the liner supported thereby in suspended relation from the casing; a seal ring carried on the liner upwardly adjacent to said stop ring providing radially contracted and expanded positions; and expander ring borne by the liner above the seal ring for engagement therewith to actuate said seal ring to said expanded position in tightly sealing relation against said casing upon initial engagement of said stop ring with said stop collar, and said liner being axially slidable through said stop ring, said seal ring and said expander ring during said thermal fluctuations in the well; and a plurality of resiliently flexible fingers mounted on said liner in downwardly axially spaced relation to said stop ring being expandable against said casing in sliding relation therewith to center the liner within the casing and being engageable with said stop collar to limit upward travel of said liner within the casing.

8. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination baflle plate and liner hanger stop collar rigidly mounted in predetermined position within said casing and including an annular shoulder extending radially inwardly thereof; a liner hanger having an annular stop ring disposed in circumscribing relation about the liner for engagement with said stop collar to limit downward travel of the liner relative to the casing; a plurality of shear pins rigidly connecting said stop ring to the liner temporarily supporting the same in suspended relation from the casing; a seal ring loosely carried on the liner upwardly adjacent to the stop ring; and a drill tubing string connector sleeve screw threadably mounted on the liner to expand the seal ring in tightly sealing relation against said casing during relative downward movement of the liner sleeve incident to the shearing of said shear pins upon the imposition of the full weight of the liner thereupon as said stop ring engages the annular shoulder of the stop collar, and said liner being axially slidable through said stop ring and said seal ring during said thermal fluctuations in the well.

9. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well and for accommodating thermal fluctuations in the well, comprising a combination baffle plate and liner hanger stop collar rigidly mounted in predetermined position within said casing and including an annular shoulder extending radially inwardly thereof; a liner hanger having an annular stop ring disposed in circumscribing relation about the liner for engagement with said stop collar to limit downward travel of the liner relative to the casing; a plurality of shear pins rigidly connecting said stop ring to the liner for temporarily supporting the same in suspended relation from the casing; a seal ring constructed of a relatively soft metallic material having an inner periphery providing a pair of spaced annular V-shaped grooves with the seal ring loosely carried on the liner upwardly adjacent to the stop ring and being radially contractible for initial introduction into the casing in frce sliding relation within the casing and radially expandable therein; and a drill tubing string connector sleeve screw threadably mounted on the liner being engageable with said seal ring to expand the same with said grooves insuring uniform expansion of the seal ring in tightly sealing relation against said casing during relative downward movement of the liner sleeve incident to the shearing of said shear pins upon the imposition of the full weight of the liner thereupon as said stop ring engages the annular shoulder of the stop collar, and said liner being axially slidable through said stop ring and said seal ring during said thermal fluctuations in the well.

10. An apparatus, for slidably suspending a production liner from a well casing in spaced relation to the bottom of a well for accommodating thermal fluctuations in the well, comprising a combination baffle plate and liner hanger stop collar rigidly mounted in predetermined position within said casing and including an annular shoulder extending radially inwardly thereof; a liner hanger having an annular stop ring disposed in circumscribing relation about the liner for engagement with said stop collar to limit downward travel of the liner relative to the casing; a plurality of shear pins rigidly connecting said stop ring to the liner temporarily supporting the same in suspended relation from the casing; a seal ring loosely carried on the liner upwardly adjacent to the stop ring being radially contractible for initial introduction into the casing in free sliding relation within the casing and radially expandable therein, said seal ring forming an annular space when disposed in said expandable position between the liner and the seal ring; an annular expander ring disposed in circumscribing relation above said seal ring during initial introduction of the liner within the casing; and a drill tubing string connector sleeve screw threadably mounted on the liner being engageable with said expander ring to force the expander ring into said space between the liner and the seal ring to expand the same in tightly sealing relation against said casing during relative downward movement of the liner sleeve and expander ring incident to the shearing of said shear pins upon the imposition of the full weight of the liner thereupon as said Stop ring engages the annular shoulder of the stop collar, and said liner being axially slidable through said stop ring and said expander ring during said thermal fluctuations in the well.

11. A method of completing a well having an elongated casing, comprising the steps of disposing a combination batlle plate and liner hanger stop collar within the casing in predetermined position therein; installing within said collar in tightly fitted relation a bafile plate with the plate serving as a stop for a packing tool employed to force cement and the like downwardly within the casing and thence upwardly around said casing; removing said plate from the collar by drilling through the collar to clean the casing preparatory to the introduction of production equipment into the casing; attaching a production liner to the drill string by way of a liner hanger; inserting said liner, liner hanger and drill string into the casing with the liner extended through said collar; and setting said hanger on said collar to suspend the liner from the casing in spaced relation from the bottom of the well with said hanger permitting substantially unrestricted upward travel of the liner relative to the casing in response to thermal fluctuations occurring in the well.

12. A method of completing a well having an elongated casing disposed therein providing a lower end, comprising the steps of disposing a combination bafile plate and liner hanger stop collar within the casing in predetermined spaced relation adjacent to said lower end of the casing; installing within said collar in tightly fitted relation a bathe plate with the plate serving as a stop for a packing tool employed to force cement and the like downwardly within the casing and thence upwardly around said casing; removing said plate from the collar by drilling through the collar to clean the casing preparatory to the introduction of production equipment into the casing; attaching a production liner to the drill string by way of a liner hanger having a seal ring disposed about the liner in collapsed condition; inserting said liner, liner hanger and drill string into said casing with the liner extended through said collar; setting said hanger on said collar to suspend the liner from the lower end of the easing in spaced relation to the bottom of the well; forcing said hanger against the seal to expand the same against said casing; and permitting said liner axially to slide through said seal relative to the casing in response to thermal fluctuations occurring in the well.

13. A method of completing a well having an elongated casing disposed therein providing a lower end, comprising the steps of disposing a combination baflle plate and liner hanger stop collar within the casing in predeermined spaced relation adjacent to said lower end of the casing; installing Within said collar in tightly fitted relation a battle plate with the plate serving as a stop for a packing tool employed to force cement and the like downwardly within the casing and thence upwardly around said casing; removing said plate from the collar by drilling through the collar to clean the casing preparatory to to the introduction of production equipment into the casing; attaching a production liner to the drill string by way of a liner hanger having a seal ring disposed about the liner in collapsed condition, said liner hanger including a plurality of shear pins for connecting the hanger to the liner; inserting said liner, liner hanger and drill string into said casing with the liner extended through said collar; setting said hanger on said collar to suspend the liner from the lower end of the casing in spaced relation to the boitorn of the well; forcing said hanger against the seal by shearing said pins to expand the seal ring against said casing; and permitting said liner axially to slide through said seal relative to the casing in response to thermal fluctuations occurring in the well.

Reiei'ences Cited UNlTED STATES PATENTS 226,185 4/1880 Newell et al 166-181 1,598,794 9/1926 Warren 16689 1,997,312 4/1935 Satre 166-46 2,310,572 2/1943 Burns 166124 2,671,512 3/1954 Ragan et al. 166182 2,707,997 4/1955 Sandmer et al. 16646 2,905,249 9/1959 Ownbey 166-181 3,273,646 9/1966 Walker 166--86 JAMES A. LEPPINK, Primary Examiner. 

